As the size and cost of integrated circuits have continued to progress downward, microprocessors have been incorporated into an ever increasing range of devices. Specifically, one market segment which has seen significant growth is the area of smart cards. One of the first applications for smart cards was debit cards, making it possible to implement more secure payment systems.
Like integrated circuits, the form factor and cost of wireless components have seen a similar downward progression. With advancements in technology and manufacturing, contactless smart cards have begun to proliferate. Often, these contactless smart cards are passive, with no internal power supply, and thus are powered wirelessly via a magnetic field or through other means. Alternatively, a small battery may be embedded as a power supply.
One of the primary growth areas for contactless smart card applications is presentation instruments, such as credit or debit cards. When such presentation instruments are activated (perhaps by a magnetic field produced by a scanner or other point-of-sale device), a user's account information stored thereon may be transmitted via radio signal. Because of this wireless activation and transmission, in many instances there may be an increased risk of theft or other abuse. Components are available which can be configured to snoop or otherwise collect the account information contained in the signals.
Typically, such radio signals transmitted from smart cards are encrypted. However, increasingly sophisticated technology is being developed to evade this protection. Hence, for these and other reasons, there is a need for alternative methods that provide for improved security for wireless presentation instruments.